/*
   Copyright (c) 2015 LinkedIn Corp.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package com.linkedin.multipart;


import com.linkedin.r2.message.stream.entitystream.Writer;

import java.util.Map;


/**
 * Interface that is required to be implemented by custom data sources when constructing a
 * {@link com.linkedin.multipart.MultiPartMIMEWriter}.
 *
 * @author Karim Vidhani
 */
public interface MultiPartMIMEDataSourceWriter extends Writer
{
  /**
   * Immediately return the headers need for this part. If no headers are provided, clients must
   * return an empty map.
   *
   * @return a Map representing the headers for this data source.
   */
  public Map<String, String> dataSourceHeaders();
}